[JAVA3D] SingularMatrixException in Transform3D.invertAffine()

[Mark Crompton]

Hi all,

I'm currently trying to add collision detection to my Java3D project, a
little Lego editor.  When the user picks a 'brick' to move, I add a behavior
with a WakeupOnCollision tied to the brick's branch group.  As soon as I do
this I get the exception below.

Can anyone shed any light on what causes a SingularMatrixException?  I've
had a look at http://mathworld.wolfram.com/SingularMatrix.html, but am still
none the wiser.

javax.vecmath.SingularMatrixException: cannot invert matrix
        at javax.media.j3d.Transform3D.invertAffine(Transform3D.java:2826)
        at javax.media.j3d.Transform3D.invert(Transform3D.java:2682)
        at javax.media.j3d.GeometryRetained.intersect(GeometryRetained.java:252)
        at
javax.media.j3d.Shape3DRetained.intersectGeometryList(Shape3DRetained.java:2
062)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:362)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:385)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:385)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:385)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:385)
        at javax.media.j3d.BHTree.doSelectAny(BHTree.java:392)
        at javax.media.j3d.BHTree.selectAny(BHTree.java:344)
        at javax.media.j3d.GeometryStructure.collide(GeometryStructure.java:1044)
        at
javax.media.j3d.GeometryStructure.addWakeupOnCollision(GeometryStructure.jav
a:748)
        at
javax.media.j3d.WakeupOnCollisionEntry.addBehaviorCondition(WakeupOnCollisio
nEntry.java:337)
        at javax.media.j3d.WakeupCriterion.buildTree(WakeupCriterion.java:67)
        at
javax.media.j3d.BehaviorStructure.activateBehaviors(BehaviorStructure.java:3
45)
        at
javax.media.j3d.BehaviorStructure.processMessages(BehaviorStructure.java:210
)
        at
javax.media.j3d.StructureUpdateThread.doWork(StructureUpdateThread.java:83)
        at javax.media.j3d.J3dThread.run(J3dThread.java:256)

Thanks,
Mark Crompton

http://sourceforge.net/project/jlug

===========================================================================
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff JAVA3D-INTEREST".  For general help, send email to
[EMAIL PROTECTED] and include in the body of the message "help".